A man who authorities say killed his ex-girlfriend Saturday in Woodridge with a knife he received from her as a present was ordered held without bail today on murder and sex assault charges.

Adam Belmont was charged in the weekend stabbing death of Alyssa Van Meter, 25, of Woodridge, and appeared at a Monday afternoon hearing before DuPage County Judge Alex McGimpsey, who denied bail after hearing prosecutors outline how Belmont climbed a balcony to enter his girlfriend’s apartment before he killed her.

Once inside, Belmont confronted Van Meter, who had ended their relationship, Assistant State’s Attorney Tim Diamond said. Belmont later choked her and then stabbed her to death before sexually assaulting her, Diamond said.

Prior to the attack, Van Meter had sent a text message to her new boyfriend about 9:30 p.m. Saturday night, according to prosecutors.

Van Meter’s brother discovered her body later Saturday night in her bedroom at the apartment in the 2400 block of Forest Drive where she and the brother lived. Prosecutors said Belmont, 23, had previously lived there, too, but had moved out after his relationship with Van Meter ended about a week ago, Diamond said.

Woodridge police traced Belmont to his mother’s home in Northlake, Diamond said, and he was taken into custody later the same night.

Over the next 24 hours, the prosecutor said, he gave several statements describing what had happened. Friday night, Belmont came to the apartment to talk to Van Meter and before he left, he placed a knife on a shelf in her bedroom. It was a gift from Van Meter and had their names inscribed on it, along with an anniversary date, Diamond said.

Saturday night, Belmont returned and scaled a balcony support to reach the second-floor apartment. He then used a different knife to slice through a screen and enter via an unlocked window. Van Meter confronted him, they spoke for several minutes, and when it appeared she would not be willing to get back together, Belmont “snapped” and choked her into unconsciousness, Diamond said.

When Van Meter started to regain consciousness, Belmont took the gift knife from the shelf and stabbed her once in the chest, piercing her heart. He then removed most of her clothing before he stripped and sexually assaulted her, prosecutors said.

Police recovered a bloody knife and a set of Van Meter’s keys at a shed at his mother’s house. During a police interview, Belmont told authorities that he put the items there, Diamond said.

Van Meter and her brother both worked as tow truck operators. She had recently been in the New York area volunteering with relief efforts for Hurricane Sandy victims, authorities said.

In addition to first-degree murder and aggravated criminal sexual assault, Belmont is also charged with felony murder and home invasion.

Before this afternoon, authorities had released no information about Van Meter's slaying, although it took place Saturday.

"We knew early in the investigation that this was an isolated incident which led us to the victim’s ex-boyfriend," Woodridge Police Chief Ken Boehm said in the release. "At no time was public safety at risk."